The 'Barwon South West Regional Dairy Supply Chain Study' report presents a case for investment in roads infrastructure to support the future of the south-west's dairy industry.

The document has been two years in the making with input from all levels of the dairy industry supply chain.

It found trucks currently cart over 61 million tonnes of milk outbound and supply inbound per year.

With dairy production and processing in the south-west expected to increase to 2.5 billion litres or 89.8 million tonnes, the report report identifies the Princes Highway as the network spine as the main east-west link between farms, processors and the gateway to-market.

It recommends the following roads, which carry the highest volumes, connect processing centres and provide market access, be prioritised for funding:

They make up the principal network which provide access for vehicles up to 85.5 tonnes each.

Dairy farmer Simon Craven, of Ecklin, helped put together the region-wide investigation into the poor condition of the roads and the ramifications for the south-west dairy industry.

Mr Craven made an impassioned speech at the June 25 Corangamite Shire Council meeting, where the report was adopted with full support from councillors.

"This has been a massive team effort, we've been screaming at the state government to get our roads fixed," he said.

"Now that we have the correct data on paper we have to make them accountable and make sure they read it, and that it becomes second-nature to them.

"We've been ignored for way too long."

Mr Craven said he almost didn't make it to the Tuesday meeting because his prime mover lost crucial bolts and springs on the rough roads.

"I nearly didn't make it because my truck had two broken bolts in the suspension," he said.

"I'm fixing broken springs and bolts at unheard of rates and I only have one truck, I'd hate to have multiple trucks.

"The dairy industry makes a lot of dollars that haven't come back to our region.

"We need to make sure the message is sent loud and clear to Spring Street."

A letter and copy of the report will be send to state parliament, pushing for investment in roads infrastructure in the south-west.

Dairy industry representatives along with state and local government stakeholders worked together on the project, giving an evidence base to the value of the dairy industry to both the state and national economies.

It drives home the need for investment in the south-west road network.

The south-west dairy industry is the largest single-employer in the region, making up close to 24 per cent of the national milk production and 27 per cent of Australia's dairy exports.

It employs around 7000 workers on farms and provides more than 10,000 jobs in the industry.

The region has around 1300 farms and is home to some 392,000 cows.

By 2045 an additional 47 per cent of total tonnage will be carted across the network, up to 89.8 million tonne.

"The road network plays a critical role in the dairy supply chain, providing the first and last mile link between the farm gate and processor for raw milk collection," the report reads.

"As well as road based freight movements associated with raw milk collection, delivery of cattle, hay, fertiliser and other inputs add to the overall freight task.

"Making the recommended $317.5 million investment over 10 years, and assuming switching to High Productivity Freight Vehicles (HPFV) at the same rate will increase fleet capacity by 20.4 per cent which will underpin significant potivie outcomes for the industry and the economy more generally."

The cash would resurface, rehabilitate or widen roads across 646 kilometres of arterial roads and 130 kilometres of local roads.

That figure also includes the strengthening and replacing of bridges.

The report shows the investment would benefit the entire dairy supply chain and provide a competitive outcome through lower transportation and freight costs, which total over $53 million by 2025.

The project was led by Corangamite Shire in partnership and with funding from the Victorian government and Colac Otway Shire, Moyne Shire, Southern Grampians Shire, and Warrnambool City Council.

A letter will be sent to Minister for Roads, Road Safety and TAC Jaala Pulford and Minister for Ports and Freight Melissa Horne.

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